Method for manufacturing printed wiring board

Abstract

Quickly making changes to etching conditions suppresses the production yield of printed wiring boards from being deteriorated. Disclosed is a method comprising: an etching step that comprises: preparing a conductor-clad base material continuous in a certain direction, the conductor-clad base material ( 1 ) having an insulating layer and one or more conductive layers formed on main surfaces of the insulating layer; and subjecting a predetermined region of a conductor layer of one main surface of the conductor-clad base material ( 1 ) to an etching process thereby to form a wiring pattern ( 1 a ) to be of a product and an inspection pattern ( 1 b ) to be used for inspection; a measuring step that measures a line width of the inspection pattern after the etching step; and a control step that controls an etching condition in the etching step based on the measured line width.

What is claimed is: 
     
       1. A method for manufacturing a printed wiring board, the method comprising:
 an etching step that comprises: preparing a conductor-clad base material continuous in a certain direction, supporting and carrying the conductor-clad base material along the certain direction, the conductor-clad base material having an insulating layer and one or more conductive layers formed on main surfaces of the insulating layer; and subjecting a predetermined region of a conductor layer of one main surface of the conductor-clad base material to an etching process thereby to form a wiring pattern to be of a product and an inspection pattern to be used for inspection; 
 a measuring step that measures a line width of the inspection pattern after the etching step; and 
 a control step that controls an etching condition in the etching step based on the measured line width; 
 wherein the inspection pattern comprises a plurality of line-like patterns parallel to one another along the certain direction, and wherein each of the line-like patterns has a predetermined line width; 
 wherein, when each difference between line widths of the plurality of line-like patterns is less than a predetermined value, then the control step controls the etching condition based on the line widths of that plurality of line-like patterns, whereas when each difference between line widths of the plurality of line-like patterns is more than or equal to the predetermined value, then the control step determines that plurality of line-like patterns as not being the inspection pattern and stops controlling the etching condition based on the line widths of that plurality of line-like patterns and continues an immediately previous control. 
 
     
     
       2. The method for manufacturing a printed wiring board as set forth in  claim 1 , wherein the control step refers to correspondence information which preliminarily associates the line width of the inspection pattern and the etching condition in the etching step with each other, and wherein the control step controls the etching condition based on the measured line width. 
     
     
       3. The method for manufacturing a printed wiring board as set forth in  claim 1 , wherein the inspection pattern comprises three or more line-like patterns. 
     
     
       4. The method for manufacturing a printed wiring board as set forth in  claim 1 , wherein the inspection pattern includes inspection patterns positioned at different positions in substantially perpendicular direction to the certain direction, and
 the control step controls etching conditions corresponding to respective inspection patterns based on line widths of the respective inspection patterns measured in the measuring step. 
 
     
     
       5. The method for manufacturing a printed wiring board as set forth in  claim 1 , wherein the measuring step takes an image of the inspection pattern from one main surface side of the conductor-clad base material in a state of the inspection pattern being exposed to light from other main surface side of the conductor-clad base material, and measures the line width of the inspection pattern based on the taken image. 
     
     
       6. The method for manufacturing a printed wiring board as set forth in  claim 1 , wherein the measuring step emits laser light from one main surface side of the conductor-clad base material to the inspection pattern and measures the line width of the inspection pattern based on transmitted light of the laser light.